Wild, I did a science fair experiment on plant growth vs light color as a young kid! i had each plant in a different shade of upside down tumbler cup and compared the growth. N=1 for each cup, but I remember being surprised that the plants really didn’t seem to care when you filtered out certain shades.
One thing the article doesn't mention is that some plants prefer a little shade.
So while broccoli yeilds may have "held steady," it's possible they could make even more gains elsewhere. So leafy vegetables like spinach might be doing equivalently fine under the magenta shades in New Jersey, but might actually be even better in Texas.
There are countless square miles of vacant land in the USA that are unsuitable for farming and ideal for solar. This might be useful in areas where vacant land is actually scarce.
I find the physics of wavelength-dependent materials properties oddly satisfying. You can do clever things like this, extracting energy from different parts of the spectrum by combining materials and conversion processes. You can beam waste heat back to space through the atmosphere’s “infrared window”. You can explain global warming from first principles. Fascinating stuff!
I'm current taking composite construction certification courses because modern manufacturing provides for customizing the material for very specific uses. Low volume production with very specific mechanical and physical properties.
I feel the same way about how fiber optics can create bandwidth by just slicing up the spectrum for different channels of data (my rudimentary understanding anyway). I like how even after all this time we find new and clever ways to work with light.
CdTe panels are limited by availability of tellurium. Maybe we'll mine that in space one day; much of the Earth's Te was lost as volatile H2Te. The abundance of Te in carbonaceous chondrites is about 1000x that in the Earth's crust.
I'd love this for a home greenhouse... I live in an area where during the summer insolation is high enough that some combination of large amounts shading and airflow (wasting humidity) is needed... wavelength-selective shading seems like an interesting idea to start with, and energy recovery from it is a nice add-on.
For a larger greenhouse a mix of clear non solar and solar pv pannels optimised for different plants could be the way to go.
The polycarbonate clear pannels are actualy cheap and likely strong enough that I am considering mounting solar pv directly to them. So: scratch building a greenhouse frame, that will support all the loads, and attaching the panels, and run the wires right through the polycarb, standard solar pannels, install@40" width and that works out to 3 per 12', 12 pannels for 40', for a neat eve to eve install.
Economics would suggest full spectrum panels on the outside + LED-lights on the right spectrum on the inside will always be more affordable than specialized panels. You still need lights with magenta panels to hit 18+hrs of light a day. Once the lights are already installed, specialized panels would be hard to justify a mark-up.
> Economics would suggest full spectrum panels on the outside + LED-lights on the right spectrum on the inside will always be more affordable than specialized panels.
Lookup the energy needs to grow plants, panels are like 25% efficient, you'd need to put most of it back into the LEDs to grow anything. Growing LEDs aren't your regular 5w home light bulbs, you need a lot of energy to grow plants.
I was thinking this further through. What you write was indeed the next thought… and the reason we don’t grow in multistory factories is… cost! So sunlight is the OG for greenhouse growing. Cost of m2 free ground or glass do not matter when compared to building space, lights and energy.
This does lead me back to the idea that to cover greenhouses with translucent panels, you would need translucent panels to have undergone a price drop comparable only with regular panels. Which is unlikely. And then you have risks like hail risks that multiply when covering greenhouses with panels. Although that might be an upside, since greenhouses in NL are actively going towards break free glass which is pretty expensive. So perhaps there is a break free translucent solar panel upgrade route that could work out. (I am sceptical, but it is a nice idea indeed. Light is a spectrum and not all light is equal in photosyntesis.)
I think the question is, are these panels less expensive than taking normal panels, maybe with LEDs to help growth at night, and adding solar tracking to optimize solar generation, plant shading, and plant growth?
So while broccoli yeilds may have "held steady," it's possible they could make even more gains elsewhere. So leafy vegetables like spinach might be doing equivalently fine under the magenta shades in New Jersey, but might actually be even better in Texas.
Lookup the energy needs to grow plants, panels are like 25% efficient, you'd need to put most of it back into the LEDs to grow anything. Growing LEDs aren't your regular 5w home light bulbs, you need a lot of energy to grow plants.
This is the classic out of depth HN take
This does lead me back to the idea that to cover greenhouses with translucent panels, you would need translucent panels to have undergone a price drop comparable only with regular panels. Which is unlikely. And then you have risks like hail risks that multiply when covering greenhouses with panels. Although that might be an upside, since greenhouses in NL are actively going towards break free glass which is pretty expensive. So perhaps there is a break free translucent solar panel upgrade route that could work out. (I am sceptical, but it is a nice idea indeed. Light is a spectrum and not all light is equal in photosyntesis.)